Finisher arrangements for surface finishing of parts by effecting movement of parts within media contained within an upwardly-opening bowl-shaped finishing apparatus are well known, and the finishing operation carried out by such apparatus is well understood. Frequently such finishing apparatus is provided with suitable associated hardware, including mechanisms, to facilitate loading, as well as unloading, of parts and media into or out of the bowl. Such arrangements have typically employed a container or hopper arrangement for permitting media and/or parts to be deposited therein, with the hopper then being moved to permit the parts to be discharged through the upper open mouth of the bowl into the finishing chamber. The movement of the hopper has, in known instances, employed swinging arms which enable vertical swinging of the hopper from a lowered filling position into a raised position above the finishing bowl for permitting discharge of the hopper contents. Such apparatus is also known wherein the finishing bowl itself is mounted for vertical swinging movement to permit the contents thereof, upon completion of the finishing operation, to be discharged from the bowl back into a hopper. In this known arrangement, however, the hopper and the bowl are provided with separate swing arm mechanisms which move about wholly separate and distinct swing axes. In addition, the swinging mechanisms associated with the hopper and the finishing bowl are independently driven by separate power devices. This arrangement results in the overall arrangement being of greater size and bulk, of greater structural complexity, and hence of greater overall cost.
Arrangement of the aforementioned type have caused the parts, when discharged from the hopper into the finishing bowl to be dropped vertically through a substantial distance, and a substantial vertical drop is also normally encountered when the finished parts are discharged from the bowl back into the hopper. This significant vertical dropping of the parts during transfer has been observed to cause undesirable hitting and impacting of the parts against one another, which can be damaging to the surface finish of the parts, particularly in the case of delicate and/or high precision parts.
In addition, in the apparatus of the aforementioned type, the rotor adjacent the bottom of the finishing bowl is typically rotated only throughout the actual finishing operation, but is maintained stationary during loading of the parts into the finishing bowl, and is also maintained stationary (i.e., non-rotating) when the bowl is swingably moved into a discharge position. This stationary condition of the bowl rotor, however, is believed to cause the parts, when deposited into or discharged from the bowl, to be transferred under conditions which results in more contacting and impacting of the parts with one another.
Accordingly, it is an object of this invention to provide an improved finisher arrangement for parts, which finisher arrangement includes a centrifugal-type finishing bowl having improved mechanisms and hardware associated therewith to facilitate swinging movement of both a hopper and the bowl to facilitate respective loading and unloading of parts and finishing media. The overall arrangement of this invention is believed to provide improved structural and operational simplicity, and more specifically a smaller and more compact overall arrangement which facilitates operation of the arrangement and provides improved access and visibility.
It is also an object of this invention to provide an improved operational process for such arrangement, which process includes maintaining slow rotational movement of the bowl rotor both when parts and media are deposited into the bowl, and when the bowl is in its raised and tilted position to discharge the parts and media into a collecting structure. The slow rotation of the rotor, both during loading and unloading of the bowl, and its action on the parts and media within the bowl, is capable of effecting greater spreading of the parts over the bottom of the bowl, rather than permitting the parts to bunch more closely together such as typically occurs when rotor rotation is stopped. This slow rotation of the rotor hence prevents the parts from being deposited or discharged in a large mass, but rather spreads the deposited or discharged the parts more uniformly over the depositing or discharge time cycle, thereby minimizing impacting between the parts when they undergo the transfer motion.
A further object of the invention, as aforesaid, is to provide the overall arrangement with minimal vertical drop between the bowl and the hopper arrangement, both when the hopper is positioned over the bowl to permit deposit of parts and media therein, and when the bowl is positioned in tilted relationship above the hopper assembly to discharge parts and media thereto. This minimal discharge or drop distance is particularly achieved in the arrangement of this invention by supporting the hopper in a geometric relationship relative to the bowl so that, when the hopper is swung upwardly into position over the bowl, the lower part of the hopper projects downwardly into the interior of the finishing chamber defined by the bowl. This relationship, combined with the provision of an openable discharge passage defined at the bottom of the hopper, permits the parts and media to be vertically dropped a very small and substantially minimal distance when deposited from the hopper onto the bottom wall of the bowl.
Other objects and purposes of the invention will be apparent to persons familiar with arrangements of this general type upon reading the following specification and inspecting the accompanying drawings.